Not A Pleasent Experience
I bought my PS2 2 years back which is model no SCPH - 50004. My main motive was games but i did considered watching DVD movies on that. From gaming point of view i simply adore it as it has bring some colors in my life. Really ! But watching DVD on it has not been a pleasent experience. I first tried to played Kal Ho Na Ho. It played flawlessly half of the time but then it started showing movies like a powerpoint presentation. I meant to say that there were some hiccups while playing the movie. I thought there was some problem with the DVD, hence i tried to play it on one of my friends DVD Player and it ran smoothly there. After that i tried playing more some DVDs (All of them original). Some played smoothly and some with as usual hiccups. Since Then i havnt used my PS2 for DVD movies. I rather watch them on DVD drive. Audio CDs on PS2 run without any problems.
So my suggestion would be to treat PS2 just as a wonderful game machine. On another hand its just a mediocre DVD Player. Go for some branded name while purchasing a DVD Player like Phillips, LG, Samsung etc.